An eagle cast its shadow over Silvius’ eyes as he gazed at the sun sinking behind the hills. The raptor hung on a thermal for a moment, before swooping down onto its prey, out of sight.

Silvius turned his attention back to the dusty, stony road spooling out eastwards in front of him, past the marshes and into the wooded, grey-green hills. He adjusted the leather straps of his helmet, which was beginning to weigh down on his black curls, and paced the length of his wall patrol once more. High wooden palisades, taller than he was, rose on either side of a narrow path.

He’d been on duty since the early afternoon, whilst the citizens of Lavinium went about their business below him, safe within the wooden city walls, bartering, selling, sharing jokes, starting fights, solving them. The sound of saws cutting through wood was constant, of timber being hauled and stone being hammered. The smell of sawdust carried to him on the breeze.

There had only been a few traders, coming from the other small settlements scattered near Lavinium, bringing deer skins, bear pelts, wines, olive oils, clay jars and bronze weapons. Silvius’ older brother Iulus had arrived with a party of riders from his nearby colony of Alba Longa, strutting in on a fine dark stallion. Silvius had watched him, unnoticed, from above.

Silvius longed for something more. Maybe a raiding party, bronze spears glittering like stars. Or better still, if he could see one of the creatures that his father Aeneas talked about with wonder. Aeneas said he’d seen one of the last of the fauns after a boar hunt earlier that year, shy, awkward, and beautiful, disappearing into the woods, human head and torso shading into the shaggy legs of a goat.

But Silvius hadn’t yet been allowed to fight, even in a skirmish, though it was his thirteenth birthday soon, and he was going to be given his first sword.

It wasn’t fair. Iulus had been leading the army by the time he was fourteen, when the Trojans had first come to Italian soil, fifteen years ago now, after their long journey over the seas after their city had been burnt to the ground by the Achaeans.

Silvius lifted his spear, sighting along its length as if about to hurl it at an imaginary opponent; he shouted “Yah!”, and then let it drop to his side.

Almost twilight, and time for his watch to end. The stars were beginning to glimmer, and Silvius stood for a second watching them. His favourite was Orion, the hunter, and he looked for the three stars that made up his belt, before feeling for the studded leather one that held his own tunic together.

He was looking forward to going home, where a bowl of warm venison stew would be waiting for him. Then he would go to the small wooden room he shared with his younger brother Brutus, and his hard, straw-covered bed.

Turning to go, his eye was caught by movement in the distance.

At first he thought it might be another merchant, rushing late towards the city, eager to get into the walls before the gates were barred. It was no good to be out after dark.

He looked again. The rider was moving fast, faster than any he’d ever seen before, even at the games they held for funerals. Was he running from something?

The horse’s hooves were kicking up a huge cloud of dust, pounding the dirt road, and in the dying light it was harder to make anything out. He squinted.

The rider’s chest was bare, which was odd.

There was also something strange about the horse’s movement. It was maddened, clearly, but also totally in control, the rider seeming a part of it, to flow with it in a way that showed mastery.

Horse and rider came to the end of the straight section of road that led to the city gates. The rays of the setting sun gleamed off the horse’s chestnut flank.

A horn sounded nearby. Drusus, the boy on duty on the other side of the gates from Silvius, was making the alarm. A shout went down to the guards below. ‘Close the gates! Bar them! Stranger approaching!’

Silvius heard the hinges beginning to creak shut.

‘Let me in!’ came the rider’s voice, loud, foreign and deep. ‘Let me in!’

As the sun went down, and the bright moon’s shining beams took over, Silvius realised that coming up the road at full gallop, was a centaur. How could it be? The centaurs were all meant to be gone, ridden into the stars with the gods. Yet this was a fully grown, male centaur. Fascinated, he watched the centaur’s rippling movements.

‘Let me in!’ the centaur called again.

There was an arrow sticking out of his flesh, in his right side.

Silvius gripped the top of the wooden palisade.

He was not meant to desert his post. After a second’s agony of indecision, he went racing down the stairs to the gates.

The two guards were already drawing them shut.

‘What are you doing? Let him in!’ Silvius hung onto the banister.

‘Orders of Aeneas!’ barked one of the guards, a skinny, cold-looking man, face smeared with smuts and dust. ‘No strangers after twilight. And that is definitely a stranger.’

Silvius couldn’t let that happen. He had to see this centaur, talk to him, find out what he wanted. So he leapt down the final two steps to the dusty ground, and pushed his way in front of the guards.

The other one, thickset and dark, muscles bulging as he heaved the bolt across, turned to swat him away.

And that gave Silvius enough time to dodge him, set his shoulder to the bolt, push it upwards, and kick the left hand gate open as hard as he could.

‘What are you doing?’ shouted the thickset guard, roughly. ‘I’ll have you up before Aeneas! You’re deserting your post!’

But before the guard could say anything more, the centaur was through the gap and into the city, scattering the dispersing citizens. The guards rushed, too late, to close the gate behind him.

Silvius caught a glimpse of a long tawny mane of hair, a sweating, ridged, hairy torso, and a steaming chestnut flank, bloodied and foaming.

The magnificent being swayed, and then, his front forelegs crumpling, he fell to the ground, sending dust flying upwards, his noble head crashing into the dirt.